Rotary take-up for sewing machines



Mafch 1.3, 1945.

A. N. HALE ROTARY TAKE-UP FOR SEWING MACHINES Filed Sept. 3, 1942 v ri/Lur L/L ale I v A m v Patented Mar. 13, 1945 ROTARY TAKE-UP FOR SEWING MACHINES Arthur N. Hale, Bridgeport, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J a corporation of New Jersey Application September 3, 1942,'Serial No. 457,128 16 Claims. (o1. 112-248) This invention relates to rotary thread take-up mechanisms for sewing machines and, more particularly,- to devices for "preventing abnormal winding of thread about a rotary thread take-up member.

Various expedients have been heretofore devisedto minimize and in fact to prevent abnormal Winding of thread about a rotary take-up,

member, by the provision of means for breaking or otherwise severing the thread when or after the thread begins to wind about said member. The present invention belongs in the same general category and has for its object to provide means which not only insures severing of thread winding abnormally about the take-up member, but which can also be readily assembled in thread-severing relation with respect to the takeup member.

With this and other objects in view,.as will hereinafter appear, the invention consists in the devices, combinations and arrangements of parts described in connection Withthe accompanying drawing, which illustrates a preferred embodiment of the invention and in which:

Fig. 1 is a front end elevation of the bracketarm head of a sewing machine containing theimproved thread-severingdeVice. Fig. 2 represents an enlarged view, partly in section, of the improved rear take-up member of a commercially well known double-disk take-up mechanism,'together with the improved thread-severing member associated therewith, the section being taken on substantially the line 2-2 of Fig. 1, and in a severing-element approaching position of the take-up member. Fig. 3 is a perspective view of the improved rear take-up device, with the outer thread-confining ring indicated in dot-dash lines. Fig. 4 is a fragmentary view similar to Fig. 2, but in the position ofthe take-up member in which the thread-severing element extends into the peripheral groove of said take-up member substantially medianly of the length of said groove. Fig. 5 represents an enlarged perspective view of the knife-end portion of the severing element. i

The present improvement has been embodied in a thread take-up mechanism COIIESDOIlliTlg in general to those disclosed in the U. S. Patents of S. Zonis, No. 2,191,736, February 27, 1940, and No. 2,263,533, November 18, 1941.

The sewing machine in part illustrated in the drawing has a frame including a bracket-arm head l0. Journaled for vertical reciprocation in the bracket-arm head I0 is a needle-bar H, carrying at its lower end a needle 12; said needlebar being reciprocated by any'usual or'suitable actuating connections with a horizontally disposed main actuating shaft 13.

The main shaft l3 carries at one end thereof a main or front take-up disk It provided eccentrically of the axis of rotation of the shaft 13 with a pair of radially equidistant thread-engag-r ing studs 15. The studs l5 carry a flat threadconfinin ring I6 held spaced from the disk. l4 axially of the main shaft [3. Being carried by Fig. 1 of the drawing.

The thread-controlling mechanism also includes a supplemental rear take-up device, in- I eluding a rotary shaft H disposed parallel to the main-shaft l3 and actuated as described in said prior Patent No. 2,191,736, or in any other suitable or preferred manner, to perform two rotattions for each rotation of and in the same direction as the main shaft 13; Carried by the supplemental shaft l'l for rotation therewith is a primary thread-confining element in the form of a disk 18, which is preferably disposed'in substantially the same vertical, plane as the front takeup disk I 4."

Carried by the supplemental take-up disk I8 to extend laterally therefrom eccentrically of the axis of rotation of said disk is a thread-engaging member 19 rotatable in an orbital path about the axis of the shaft IT. The thread-engaging member! 9, in turn, carries a secondary thread-confiningelementin the form of a flat ring 20 concentric with the disk l 8 and held spaced laterally therefrom by the member I 9; the ring 20 and the member I!) bein suitably secured to the disk It, as for example by a rivet 2|. The radially spaced inner and outer circumferential faces of the thread-engaging member l9 are preferably curved substantially concentrically, with the axis of rotation of the shaft 11 as the center of curvature, as illustrated in Fig. 1 of the drawing.

At its leading end, the thread-engaging member 19 is'cut away adjacent to the disk l8 to pro vide a convexly curved thread-deflecting side face 22 extending from the inner side face of the ring 20 across a plane medianly between and parallel to the disk l8 andring 20, i. e., across a central plane of rotation of the member I9. The threaddefiecting face 22 of the member [9 terminates in proximity to the disk 18 in a thread-receiving throat 23.

The trailing end of the thread-engagin mema 2,371,518: and trailing side faces extending in opposite directions across the plane of said groove, whereby an abnormal winding of thread about said member will extend across said groove, and a knife positioned to traverse said groove in the path of thread abnormally wound about said member.

5. In a sewing machine, in combination, a thread take-up device including a rotary threadengaging member rotatable in an'orbital path and having thread-deflecting side faces terminating in thread-receiving throats disposed at op-v posite sides of a substantially central plane of rotation of said member, whereby an abnormal winding of thread about said member will extend across said central plane, said member having an orbitally extending knife-clearance groove disposed in substantially said central plane, and a thread-severing knife disposed out of rangeof the thread during the normal thread-control-' ling action of said take-up member and traversing said groove during a part of the rotation of the take-up member.

6. In a sewing machine, in combination, a

rotation of said member and across said groove,

thread confining element side of said groove to terminate in a thread-receiving throat at' the primary element side of said groove, said threaddeflecting side faces extending in opposite directions from said elements, whereby thread wound abnormally about said member will be deflected across/said groove, and a thread-severing knife positioned to extend into said groove at substantially a'time in the take-up rotation cycle when said member has completed giving up slack thread. t

9. In a sewing machine, in combination, a thread-engaging take-up member having an orbital path of rotation and radially spaced peripheral faces about which the thread may abnormally wind circumferentially, and a stationary threadsevering member extending into the orbital path of rotation of said take-up member, said takeup member having in one of said faces a groove disposed toreceive said thread-severing member and extending'across an abnormal winding of thread about said take-up'member.

10. In a sewing machine, in combination, a thread-engaging take-up member having an orbital path of rotation and about which member the thread may abnormally wind circumferentiab' ly, a knife-element having a thread-severing cutting edge, supporting means for said knife providing for turning movement of said knife to pcsition said cutting edge in substantially a plane containing said orbital path of rotation of the and a stationary knife disposed out of range of the thread during the normal thread-controlling action of said take-up member and traversing said groove in each rotation of the take-up member.

7. In a thread take-up mechanism for sewing machines, in combination, a pair of substantially parallel primary and secondary thread-confining elements rotatable about a common axis, a thread-engaging member connecting said elements eccentrically of theaxis of rotation thereof, said member having a thread-deflecting side face extending from the primary thread-confining element to terminate in a thread-receiving throat at -the secondary-element side of said member, and said member having another thread-deflecting side face extending from said secondary element to terminate in a thread-receiving throat at the primary-element side of said member, whereby thread wound abnormally about said member will extend across the plane of rotation of said member, and a knife disposed out of range of the thread during the normal thread-controlling action of said member and extending into proximity to said member for severing thread wound abnormally about said member.

8. In a thread take-up mechanism for sewing machines, in combination, laterally spaced primaryand secondary thread-confining elements rotatable about a common axis, a thread-engaging member disposed between said elements eccentrically of the axis of rotation thereof andperipherally provided between said elements with an orbitally extending knife-clearance groove, said member having a convexly curved threaddeflecting side face extending from the primary thread-confining element side of said groove to terminate in a thread-receiving throat at the secondary-element side of said groove, and said member having another convexly curved threaddeflecting side face extending from the secondary take-up .member, said supporting means additionally providing for movement of said knife toward and from said orbital path, and means for securing said knife in set position to sever an abnormal winding of thread about the take-up member in the rotation of said member.

11. In a sewing machine, in combination, a

' thread-engaging take-up member having an orbital path of rotation and about which member the thread may abnormally wind circumferentiatly, said member being provided with an orbitally extending knife-clearance groove across which the abnormal winding of thread will extend, a knife-element having a cylindrical shank and having a thread-severing cutting edge offset from the longitudinal axis of said shank, supporting means for the shank of said knife-element providing for turning and endwise movement of said knife-element, and means for securing said knife with the cutting edge thereof disposed in the orbital plane of and extending into said groove.

12. In a sewing machine, in combination, a thread-engaging take-up member having an orbital path of rotation and about which member the thread may abnormall wind circumferentially, said member being provided with an orbitally extending knife-clearance groove across which the abnormal winding of thread will extend, a knife-element having a cylindrical shank and having blade-faces symmetrically converging in a cutting-edge, supporting means for said knife providing for endwise movement of the knife toward the orbital path of said take-up member, said supporting means additionally providing for turning movement of said knife to center the cutting-edge thereof in said groove, and means for securing said knife in set position.

13. A thread-severing knife for rotary takeups of sewing machines, comprising a cylindrical shank provided at one end thereof with bladefaces converging in a cutting-edge disposed substantially in coincidence with the outer face of said shank, said knife having the back face thereofxopposite-said cuttingwedge-holiaw groundf and inclined toward :the 1 free end of :saidcutting: edge;- and the meeting edges of said: blade: and; backzfacebeing cut away "to converge substantiailyzatt the .free end of'saids cutting edge; whereby theknifehas a; pointed free end.-

14;. A1 thread-controlling takev-upi uniti forr'use in connection withv sewin machinesxcomprising;

laterally: spaced and substantially: parallel mary and secondary threack-confiningxelements; and a thread-engaging member connectingrsaid elements: and :having threadedefiecting side: faces extending in opposite directions across: as plane: parallel to and betweensaidzelements; said: side faces. of the thread-engaging:membenterminat; ing in thread-receiving; throats-disposed respectively at opposite sides of; said :plane: Y

15; A thread controlling: take-up; unit. for use:

inn-connection Withsewing machines-y comprising; laterally spaced rimary and. secondary thread confining-,elements; and :a; threacbengagingvmem benconnecting said-"- elements and Deripherilly:

provided witha; groove: lengthwise disposed m a;-

member in spaced relation to t and concentrically:

with said-disk; saidmemberbeing providedin its outer face between said" disk and ringwith a groove extending circumferentiallyof said memher; and said? member being providedat opposite sides of said groove with threadqeceiving throats; opening in opposite directions.

ARTHURIN; 

